Fuel supply control valve



@Y 30, 1950 B. HAYTER Erm.

FUEL SUPPLY CONTROL VALVE 2 Sheets-Sheet 1 Filed May l0, 1946 May S, 1950 B. HAYTER ETAL 2,509,819

FUEL SUPPLY CONTROL VALVE Filed may 1o, 194e 2 sheetssheet 2 j@ fg Patented May 30, 1.95.0

FUEL SUPPLY CONTROL VALVE Bruce Hayter and Milton D. Huston, Sante Fe, N. Mex., assignors, by mesne assignments, to Breese Burners, Inc., Santa Fe, N. Mex., a corporation of Delaware Application May 1I), 1946, Serial No. 668,696

3 Claims.

The invention relates to an improvement in fuel supply control means for liquid fuel burners.

One purpose is to provide means for supplying fuel to hydroxylating pot type burners.

Another purpose is to provide fuel supply means which increase the rate of fuel flow rapidly, from the pilot stage to the intermediate stage.

Another purpose is to provide liquid fuel control means effective to prevent smoking.

Another purpose is to provide a liquid fuel control means for causing a sharply increased rate of liquid fuel flow between the pilot stage and the low or intermediate stage.

Other purposes will appear from time to time in the course of the specification and claims.

The invention is illustrated more or less diagrammatically in the accompanying drawings wherein:

Figure 1 is a vertical section taken through a' burner, with a float valve control illustrated in elevation;

Figure 2 is a partial end elevation on an enlarged scale, of the float valve unit;

Figure 3 is a plan view of the structure of Figure 2;

Figure 4 is an elevation of a float valve assembly, with parts in vertical section;

Figure 5 is a plan View of a float valve control cam;

Figure 6 is a side View of the structure of Figure 5;

Figure 1 is a side View of a modified form of control cam;

Figure 8 is a diagrammatic illustration of the operation of the control mechanism of Figures 1 and following;

Figures 9, l0, ll and 12 illustrate, partly in section and partly in elevation, a specially slotted valve stem shown at various positions of control; and

Figure 13 is a diagrammatic cam development.

Like parts are indicated by like symbols throughout the specification and drawings.

Referring to the drawings I generally indicates any suitable heater structure, in the form of an outer cylinder having supporting member 2 separated by open spaces 3. 4 is a partial closure for the bottom of the space surrounded by the drum or housing member l. It is provided with an air inlet aperture 5. 6 is a supporting ring shown as angular in cross section. Supported upon it is the hydroxylating burner pot generally indicated as 1. It includes a side wall 8 having a plurality of primary air inlets 9, spaced circumferentially thereabout and located at various distances from the top of the pot. I0 indicates a row of secondary air inlet apertures, more closely spaced, and larger in gauge, than the primary air inlet apertures. II is a flame ring centrally apertured as at I2, which partially closes the top of the pot. The pot may actually be supported upon the angle ring 6 by any suitable flange I3. I4 indicates the bottom of the pot, which is shown as slightly concave. I 5 indicates any suitable pilot piece or pilot housing which surrounds the area of admission of liquid fuel. It may be apertured as at I6, for communication with the pot interior. The wall I is upwardly continued as at I1 to surround a combustion space IB, which may be provided with suitable flue means not herein shown.. I9 is a liquid fuel supply duct adapted to deliver liquid fuel to the space within the pilot piece I5. It will be understood that at the pilot stage all or most of the fuel is vaporized within the pilot space and burns either in or at the top of the pilot space, or at the aperture I6. 20 generally indicates any suitable float valve housing, having the removable top 2 I. Liquid fuel flows therefrom along the duct I 9. Liquid fuel may be delivered to the oat chamber or housing 20, along the supply duct 22, from any suitable source not herein shown. Since they do not of themselves form part of the present invention, the float details are not herein indicated.

Liquid fuel from the float valve chamber flows through and across the valve seat structure generally indicated at 30. The valve stem 3| has a reduced bottom head 32 provided with any suitable metering slot 33. It moves in a guide 34 and is normally upwardly thrust to the limit of its permitted movement, by the coil spring 35 compressed between the bottom seat St and the valve stem cap 31. An oil flow aperture 38 is provided to permit the oil from the float chamber to reach the valve and valve seat. 40 is a knob control guide, suitably mounted on the float chamber housing 2!) for example on the removable top 2 I. Rotatable thereabout is the manual control knob 4I, having the downwardly extending side finger and pointer 42. The knob has fixed to it a stem 43 which extends through a suitable aperture in the guide 40 and carries the cam structure 44 which includes a central hub 45 and the actuating helical cam 46. The coil spring 41 is effective to hold the knob and cam in the desired downward position. 48 is a shaft downwardly extending from and concentric with the stern 43.` The shaft bears against a spring is nxed on the control arm 5 which is pivoted as at 5| on the cover 2l. rhe spring 139 carries a valve engaging abutment 52, which engages the top of themovable valve element Si. 53 is a normally fixed but adjustable element secured as at et to the top 2l and adjustable by the screw 55. U'pwardly projecting from it is the cam engaging member 55. The purpose of this cani engaging member 5t is to initially adjust the position of the valve by manipulating the screw 55, the cam member 5S may be raised up and down carrying with it the cam member il and corn.- pressing more or less the spring tif. t will be understood that the cap or control knob l -is free to move upwardly when the Yspring di' is compressed. As the knob il is rotated counterclockwise, the result of the consequent rotation of the spiral #ZS is to permit the valve 3l to be raised by the spring 35. Rotation in the opposite direction causes a resultant downward movement of the valve 3l. 51 indicates any suitable top plate provided with suitable calibration as at 'ia. As show-n in Fig. 3 this calibration includes an ofi position and a series of numbers indicated -in that figureV as'from l to '6; It will be realized that any suitable calibration may be employed. Positioned between vnumbers l and 2 is anabutment or upwardly projecting iinpeding element 58. It is shown as having steeply inclined converging edgeportions'g.. The member 5S isso, positioned that it engages the finger d2, when the knob is rotated forwardly Vfrom the number one position. The finger d2 valso has steeply inclined converging sides 42a. The sides la and 555 are so. steep that the linger B2 cannot rest on the member 58,. It` must either be positioned on oneside of it or on the other. linv eiect, the knob therefore cannot be set in a valve control position corresponding to the total width. o1"V the member '53. rlhis valve position is therefore eliminated in normal possible setting of .the valve 3|. Since the cam 46 is fairly steeply inclined, this is equivalent to cutting out a range of low otherwise represented by the space or distance occupied by the member- 53. 'I-hus lwith reference to Fig. 8, if the knobl 4lis rotated from the zero position to the 3 cc. position, the mem-- ber 58 has no effect. But when vthe member is contacted by the member 42 no valvesetti-ng is possible until the finger l2 has been liftedrover the member 58. Because of the steepness of the opposed edges 62a and 59, the next possible setting is at the 8 cc. setting of Figure 8. From then on the setting can -be changed at will. up l to the indicated maximum of.32Y cc. The actual now in cubic centimeters per minute however can be varied to suit the particular problem. Thus there is provided means for cutting out a range of setting, fromv the maximum pilot setting, to theV advantageous minimum. combustion setting.

It will be understood that the cam l5 maybe provided with a steepened area which may yperform the samel function. However, it may be somewhat morefadvantageous to havefan exterior and observable member such as.-' 8. V`

As another practical means for cuttingpart of the range of now, there is illustrated in Fig. 7

a downward offsetY t!)Y in the otherwise regular helix El of a variant form. of` cam. The dow-nthe rate of flow of the form of Fig. 7 is also properly indicated in the diagram of Fig. 8. The range between 3 cc. to 8 cc. is simply cut out.

The same result may be obtained by a special form of valve metering aperture. Figs. 9 to 12 should be considered in connection with Fig. 4. In Fig. 4 the metering aperture 33 is shown -as of uniform -width from top to bottom. In the form of Figs. 9 to 12 the valve slot has an upper reduced portion 33a and a lower laterally enlarged portion 33h.. As the knob is rotated, and is forced by the member 58 to make a substantial eXtra jump, the valve stem is rather sharply raised to increase .the flow.- It will be understood, of course, that any means for forcing this jump in the position of the knob can be used. If the formation of the metering slot of Figs. 9 to 12 is used with the finger l2 and the interrupter 58, the result is indicated in the various positions of the valve. Figure 9 illustrates the zero position, when the pointer ris at the oit position. When the `pointer is movedutovvard numeralf2 and somewhat beyondv the numeral 1 position the cam is effective to. raise 'the consumption-from zero! cc. to '3, cc., with reference to-lilig. '13. The cam effect of the. member ysforcesfa rotation of' theknob M toa'position in which thenngerfu is beyond the member 58. The resultant of the yvalve makes an abrupt change inthe .efiective diameterofthe meteringl slot. Whereas up to 3 cc. atione side of ythe i-nterrupter-5-8 only the narrow portion 33a is effective, the :lifting of' the knob `to position the linger 1&2 beyond the inlterrupter 58 depresses the `knobto position bef yond the interrupter tvraising thelvalve stem to the position of Fig. 11 in :which the wide .part33b of the metering slotv begins. to pass. fuel. vThereafter, continued. rotation of .the knobl lifts the. valve stem until the top position of Fig. 12""is reached, which. may correspond to vthe 32icc..il=ow of thezdiagram of Fig. .13.

It will be realized that, whereas, we have .desscribedy and `illustrated la :practical and operati-ve device, nevertheless manyfchanges maybe made in the size, shape, number andzdispos'ition of'parts without departing from the spirit of our 'invention. We therefore wis-h your descriptionl zand drawings to lbe taken .as in a broadV senseillustrati-Ve or diagrammatic, rather than as limiting us to our precise showing.

The use and `operation. of theA invention are as follows:

In hydroxylatingf pot typeburners, when a burner pot 'l' is employed with a pilot housing-.or restrictor such. as [5, off'which various types `have been usedv by applicant, and with ythe liquid f-ueli supply delivered to restricted pilot .zot-1e, 1a rela-- tively Asmallzvolume of vfuel'. is delivered at a rate of ,from 1 cc. to 3 cc. per minute. In the particular pilot devicehereinfshown, a cleanfiblue-re is maintained in the chimney member I5, with a little-flame .at the top, wheni theminimumlow l rcc. is maintained. Ast'the ilow is increased, say to 3 cc. per minute, togive a rough illustration, there isa substantial name at .the top. of Ythe pilot l5, but the pilot is still able toztakenthe'en.- tire-volume of liquid fueras delivered, and vaporize burn it, without. leakage ofzunvaporizedliquid fuel` to the rest of the `burner,.andwithout.

smokingggr deposit offree carbon.

The threshold may vary in4 different burners, or inmdiferentsize's'of .burnenbut when the .rate of delivery increases above some-critical level; which4 maybe of the order of. 3r cc. penminute, then the pilotorl restrictor does not vaporizandburn all of the fuel, and liquid fuel flows into the outside or major portion of the interior of the pot. Assume that the rate of delivery is just above the rate which the pilot will vaporize and burn, Assume, for example, that the top limit of the pilot is 3 cc. and that the rate has risen to 4 cc. per minute, the surplus oil spills out into the main interior of the pot 'l and vaporizes and burns with a smudgy flame. There is a small flame in the big pot space, and the general air supply of the pot does not have a relation to the flame, or to the vaporized fuel, proper to maintain hydroxy-lating or two stage combustion. In other words, the characteristic initial formation of a primary mixture, and the completion of the mixture by secondary air, followed by full comlous1 tion, does not take place. Instead there is thermal decomposition, and Ia smoky llame, coupled Iwith deposit of carbon, and sooting up of the pot.

As the rate of flow increases, and more liquid fuel is being vaporized in the pot, conditions get worse, and the smudge and soot deposit increases. However, at some threshold point, which may differ in different pots and sizes, the pot begins to ll with fire, and hydroxylation begins. To take a specific example, a particular pot may have avery satisfactory pilot flame at 3 cc. and a very satisfactory combustion condition in the rest of the pot at 8 cc. or 9 cc., but an exceedingly unfavorable and smudgy condition in the range between 3 cc. and 8 or 9 cc. Once a satisfactory condition of combustion is reached, combustion may be increased, up to the maximum combustion rate of the pot.

The problem is to prevent the pot from operating in the intermediate smoky range. One solution is to cause a snap increase of the rate of flow, which cuts out the undesirable range. Although all of the liquid fuel is delivered to and through the pilot piece or Zone l5, there are several ways in which this result can be obtained. In using a rotary valve control member, with a cam the cam may be provided with a step portion so that, where it would otherwise be set within the undesirable range, it cannot readily be so set, and will drop back to a pilot setting unless the control is positively turned to pass upwardly beyond the step cam portion. However, we prefer to have the outside rotary control handle or knob 4I operate across a plate 2i having a sharp upward projection 53, to block out the undesired range, over which the finger 42 has to be lifted, so that the knob 4| cannot conveniently be set at a position which 4will cause the undesired rate or range of flow. A less eifective solution is simply to put a warning color or indication on the control calibration, so that the user is advised not to set the control within the undesired range. It is also possible to vary or control the slot outlet through which the oil flows, as in the form of Figures 9 to 12.

It' will be understood that whereas a particular pilot piece, in the form of a chimney l5 is shown, the above method and mechanism is applicable for use with a wide variety of pilot members, which can either be positioned within the pot or can be outside of the pot and in communi cation with the interior of the pot. The details or forms of these various pilot arrangements do not of themselves form part of the present invention. However, in applying the invention it is broadly necessary to have a segregated pilot area in which the air conditions for air supply are properly arranged to burn a small volume of ow of liquid fuel, which may, for illustration,

CII

advantageous to insure that at no time, for any` substantial duration, will the liquid fuel be delivered to the main combustion space :at a rate of flow sufficiently low to cause a smudgy flame. The present invention provides simple and efficient means for preventing a disadvantageously low rate of flow of liquid fuel to the main combustion zone or member, while permitting a suitably low pilot rate of flow.

A differentiation may be made between what may be called pilot flow, in which enough fuel is delivered to maintain only pilot combustion, and full combustion flow, in which sufficient fuel is supplied, for vaporization, to maintain combus-` tion in the pot at substantially above the pilot rate. Preferably but not necessarily the pilot combustion is limited to a specc and defined part of the pot space, which may be localized about the area of fuel delivery to the pot. Full combustion, in contrast, results from .a rate of flow adequate to support combustion, if not throughout the entire interior of the pot, at least across the entire diameter of the pot, and at substantially above the pilot rate. Under full combustion conditions the rate of fuel delivery may vary throughout a substantial range, but is kept above a minimum rate below which smoking and carbon deposit takes place.

We claim:

l, In a liquid flow control for burners and the like, a metering valve, yielding means tending to move it from closed to open position, a manual control means including a knob, a cam mounted on the knob for movement therewith, a fixed abutment, yielding means for holding the cam thereagainst while causing it and the knob to rise and fall responsive to movement along the abutment, connecting means between the knob and the valve whereby as the knob rotates, the valve is caused to move up and down in consonance with said rotation, the cam including an abutment engaging surface, the inclination of which is generally uniform throughout its entire length except for an interruption in the cam surface defined by two sharply inclined surfaces, inclination of such surfaces being such that as the knob is released by the operator, while the abutment engages either` of such surfaces, the abutment by engagement with such surfaces causes cam movement until abutment engages the cam on one side or the other of such inclined surfaces.

2. A metering flow control means for burners and the like, including a valve for longitudinal movement between closed position and maximum flow position, through intermediate working positions, yielding means adapted to move the valve in one direction, a manually rotatable member, a cam rigidly mounted thereon, a fixed cam abutment engaged by the cam whereby angular movement of the manually rotatable member displaces the cam and member in a direction parallel with the axis of rotation thereof, a driving connection between the manually rotatable member and the valve whereby rotation of the former in one direction overcomes the yielding means and moves the valve in one direction, and when moved in the opposite direction, relieves the pressure on the yielding means to permit the valve to move nthe opposite-:direction thecamahaving inter-` allel with the axis of rotationrthereof, efdiiving` connection/between thezmanually rotatable f membereandthevalve wherebyrotation of `the former in ione ;d-z,ection :overcomes ithe yielding means and .fmoves the valve vin onefdirecton, vamd -when moved' in the :oppositedirection; reeves: they .pressuitexon'the .yieidingrmeansto permit: the'vatve` toV 8 move 'inA the oinpositeedirection, the .cam Surface being f ofi generally vconstamtiinclination exceptafor a #short snaeintermediatedts -ends,sueh short spa-'sei being.v occpied. 4by :2,1 projectingfmenrikoerfex-` tending intofz'the path; of :the 1v abutment, fthesurfacesL ofvwhich are: too.i steep to supportftheabutment in stable-:position 'The ifeilewing `re'fez-'enees -a-re of record in'fthe fileV` of Y'this fpatent:

` STATES PATENTS 

